The actor plays rogue military intelligence soldier John Porter in Sky HD's new all-action adapation of the former SAS soldier and Ultimate Force star's hit novel.

Richard admitted: "I think there's always a pressure, especially when it's written by one of the guys that was there, that did it."

He went on: "It's useful because I can go to the book in search of the truth and find the military character, but trying to recreate that for his eyes is always going to be difficult, and knowing that there are a lot of Army guys out there that may watch this, you've always got that in your head.

"But we were working with SAS operatives who were consultants, monitoring what we were doing, making sure it was truthful, even though we're making fiction, there still has to be an element of realism to it, but at the same time you're sometimes asked to do something because it loks good for camera, but we were all over it."

But Richard, known for his role as MI5 agent Lucas North in Spooks, was pleased to be filming the action drama on location.

He revealed: "It was thrilling. It meant I was there for the whole 20 weeks, pretty much, working every day. But it was really interesting to see the different situations that they were putting John Porter into."

:: Strike Back, adapted from the hugely successful Chris Ryan novel will air on Sky1 HD in May.